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Close| target | The object to pin. This should be a managed object whose memory location needs to remain fixed during garbage collection. |
| gcHandle | The handle associated with the pinned object. Manage this handle properly to ensure it is released when no longer needed. |
void* A pointer to the memory location of the pinned object. Use this pointer for direct memory access to the object's data.
Pins an object in memory, ensuring it remains at a fixed memory location during garbage collection.
The PinGCObjectAndGetAddress method pins a managed object, preventing the garbage collector from relocating it. This is particularly useful when you need to maintain stable memory addresses while interfacing with unmanaged code or performing low-level memory operations. Ensure that you release the GC handle using UnsafeUtility.ReleaseGCObject to prevent resource leaks.
using UnityEngine; using Unity.Collections.LowLevel.Unsafe;
public class PinGCObjectBoxedStructExample : MonoBehaviour { private struct MyStruct { public int value; }
void Start() { // Create and box a struct object myObject = new MyStruct { value = 20 };
// Pin the boxed struct and get the address of its memory location unsafe { void* dataPtr = UnsafeUtility.PinGCObjectAndGetAddress(myObject, out ulong gcHandle);
// Move the pointer to skip the object header to get to the struct value int objectHeaderSize = UnsafeUtility.SizeOf<long>() * 2; // Typical object header size in bytes int* valuePtr = (int*)((byte*)dataPtr + objectHeaderSize);
// Log the initial value Debug.Log($"Initial struct value: {*valuePtr}"); // Expected output: 20
// Modify the value through the pointer *valuePtr = 40;
// Release the GC handle after manipulation UnsafeUtility.ReleaseGCObject(gcHandle); }
// Re-cast the object to a struct to verify modifications MyStruct modifiedStruct = (MyStruct)myObject; Debug.Log($"Modified struct value: {modifiedStruct.value}"); // Expected output: 40
// Confirm the GC handle is released Debug.Log("GC handle released, boxed struct unpinned."); } }
Additional resources: UnsafeUtility.PinGCArrayAndGetAddress.
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